1. Field of the Invention
The present invention relates to a perfluoroalkyleneoxy group-substituted phenylethylsilane compound and a polymer thereof and, more particularly, to a perfluoroalkyleneoxy group-substituted phenylethylsilane compound having excellent thermal and chemical stability to be solution-processed in a monomer state, a polymer prepared by thermal polymerization and having a high resistance to organic solvents, and uses thereof.
2. Description of Related Art
It is expected that an electronic circuit board that can be readily manufactured at low cost, not broken by impact but easily bent or folded, will become an essential element in the electronics industry in the future. Accordingly, the development of organic transistors that can meet such requirements has attracted much attention.
The organic transistors can be effectively used in many cases where there is a necessity to form organic elements on a wide area, where a lower processing temperature is required, where bendability is required, especially, where a low-cost process is required; however, it cannot be applied to an element, in which silicon Si, germanium Ge, and the like are employed, requiring a high speed operation due to low charge mobility in terms of characteristics of organic semiconductors.
A transistor element having excellent performance requires high on/off ratio and charge mobility. Moreover, the formation of thin film layer should be available at low temperature. This is because that it is difficult to increase the processing temperature since the glass transition temperature is very low (around 250° C. in case of polyimide) in terms of characteristics of plastic substrates. Moreover, a low current leakage is essential in terms of reliability.
Meanwhile, since a bottom-contact organic thin-film transistor prevents an organic semiconductor polymer from being contaminated in a patterning process, compared with a top-contact organic thin-film transistor, it does not deteriorate the element performance. Accordingly, a development of the bottom-contact organic thin-film transistor is required to fabricate a large-size element and thereby a development of a gate insulating material having excellent solvent resistance is necessary.
However, polymer insulating materials developed so far have a problem in that the on/off ratio is low. Accordingly, it is necessary to develop a new organic material meeting the requirements of the above-described organic thin-film transistor.
As a result of intensive studies to solve the above-described problems, the inventors of the present invention have found that a perfluoroalkyleneoxy group-substituted phenylethylsilane compound can be solution-processed in a monomer state since it has a phenethyl group, a polymerization reaction occurs based on a perfluorocyclobutene (PFCB) during the polymerization of monomers if heat is applied at a temperature below about 200° C., and the thus obtained polymer shows a high resistance to organic solvents, and completed the present invention.
Since the perfluoroalkyleneoxy group-substituted phenylethylsilane compound of the present invention has a high resistance to organic solvents, it is possible to apply a solution process to the compound. Moreover, it has been ascertained that the polymer obtained by thermal polymerization has a high resistance to organic solvents with excellent thermal and chemical stability. Furthermore, it has been found that, if the perfluoroalkyleneoxy group-substituted phenylethylsilane compound and the polymer thereof are applied to an insulating layer, the solution process can be employed due to the above-described characteristics. Especially, it has been also found that, if used as a gate insulating material for organic thin-film transistors, the perfluoroalkyleneoxy group-substituted phenylethylsilane compound and the polymer thereof have excellent thermal and physical resistance and thereby a method of manufacturing a large-size element can be applied using a photolithography process. In addition, it has been confirmed that the organic thin-film transistor in which the gate insulating material is used shows a high on/off ratio.